Method to produce a thermoplastic wear resistant foil

ABSTRACT

A method to produce a wear resistant foil, including providing a first foil including a first thermoplastic material, applying wear resistant particles and a second thermoplastic material form on the first foil, and adhering the first foil to the second thermoplastic binder and the wear resistant particles to form a wear resistant foil.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.14/790,850, filed on Jul. 2, 2015, which claims the benefit of SwedishApplication No. 1550455-8, filed on Apr. 16, 2015, Swedish ApplicationNo. 1450895-6, filed on Jul. 16, 2014, and Swedish Application No.1450894-9, filed on Jul. 16, 2014. The entire contents of each of U.S.application Ser. No. 14/790,850, Swedish Application No. 1550455-8,Swedish Application No. 1450895-6, and Swedish Application No. 1450894-9are hereby incorporated herein by reference in their entirety.

FIELD OF THE DISCLOSURE

The present disclosure relates to a method to produce a thermoplasticwear resistant foil, a method to produce a building panel including sucha thermoplastic wear resistant foil and a building panel.

TECHNICAL BACKGROUND

In recent years, so-called Luxury Vinyl Tiles and Planks (LVT) havegained increasing success. These types of floor panels usually comprisea thermoplastic core, a thermoplastic décor layer arranged on the core,a transparent wear layer on the décor layer, and a coating applied onthe wear layer. The thermoplastic material is often PVC. The wear layeris conventionally a PVC foil, for example, having a thickness of 0.2-0.7mm. The coating applied on the wear layer is conventionally a UV curingpolyurethane coating. The wear layer together with the coating providesthe wear resistance of the floor panel and protects the décor layer.

However, when subjecting floor panels to wear, it has been shown thatthe coating and the wear layer are relatively easily worn down, or atleast worn such that the appearance of the wear layer is affected, suchas having scratches and/or not being transparent any longer. Compared toa conventional laminate floor panel, the wear resistance of a LVT floorpanel is inferior. However, LVT floors offer several advantages over,for example, laminate floors, such as deep embossing, dimensionalstability related to humidity, moisture resistance and sound absorbingproperties.

It is therefore desirable to provide a LVT product having improved wearresistance. It is also desirable to simplify the build up of LVTproduct.

It is known from US 2008/0063844 to apply a surface coating includingaluminum oxide on a resilient floor covering. The coating is a wetcoating.

WO 2013/079950 discloses an anti-skid floor covering comprising at leasttwo transparent polymer layers, wherein particles of an aggregatematerial having an average particle size of between about 0.05 mm toabout 0.8 mm are located between and/or within the two or more polymerlayers. The particles improve the slip resistance of the floor covering.

SUMMARY

It is an object of at least embodiments of the present disclosure toprovide an improvement over the above described techniques and knownart.

A further object of at least embodiments of the present disclosure is toimprove the wear resistance of LVT floorings.

A further object of at least embodiments of the present disclosure is tosimplify the build up of LVT floorings.

At least some of these and other objects and advantages that will beapparent from the description have been achieved by a method to producea wear resistant foil according to a first aspect. The method includes afirst foil comprising a first thermoplastic material, applying wearresistant particles and a second thermoplastic material on the firstfoil, and adhering the first foil to the second thermoplastic materialand the wear resistant particles to form a wear resistant foil.

The first and the second thermoplastic material may be thermoplasticmaterials of different type, or may be thermoplastic material of thesame type.

An advantage of at least embodiments of the present disclosure is that awear resistant foil having improved wear resistance is provided. Byincluding wear resistant particles in the wear resistant foil, the wearresistant particles provide additional wear resistance to thethermoplastic materials of the first and the second foil. The wearresistance of the foil is improved compared to a conventional wear layerof LVT products.

Furthermore, conventional coatings, for example, a UV curable PU coatingconventionally applied on the wear layer, may be replaced by using thewear resistant foil according to the disclosure instead. A conventionalcoating step may be replaced by arranging a single foil. Thereby, theproduction process is simplified and the number of steps in theproduction process is reduced by arranging a wear resistant foil havingimproved wear resistant properties instead of several layers orcoatings.

By using different thermoplastic material in the first foil and thesecond thermoplastic material applied on the first foil, it is possibleto benefit from different thermoplastic material having differentproperties. The desired properties of the material of the first foil maydiffer from the desired properties of the thermoplastic material appliedon the first foil. For the layer formed by the second thermoplasticmaterial and the wear resistant particles arranged on the first foil,properties such as stain resistance and scratch resistance areimportant, and the choice of the thermoplastic material can be chosen tomatch these criteria. Usually, suitable thermoplastic material forforming the layer applied on the first foil may be more expensivecompared to thermoplastic material used as, for example, in printed filmor as core material. By only using such thermoplastic material in thelayer arranged on the first foil, the cost of the wear resistant foilcan be controlled. Further, the layer formed by the second thermoplasticmaterial can have a layer thickness being less than a layer thickness ofthe first foil. By choosing different thermoplastic materials for thefirst foil and the overlying layer, the thermoplastic materials can beused in an efficient and cost effective manner. By adjusting the layerthicknesses, the materials can be used in an even more efficient manner.

The object of the wear resistant particles is to provide wear resistanceof the foil when being worn, not to provide slip resistance.

The second thermoplastic material may be in powder form when applied onthe first foil.

The second thermoplastic material may be in powder form when adhered tothe first foil, such as, for example, when being pressed to the firstfoil.

The first foil, the second thermoplastic material and the wear resistantparticles may be adhered to each other by pressing the first foil, thewear resistant particles and the second thermoplastic material together.

The wear resistant foil is preferably transparent, or at leastsubstantially transparent, for example, having a light transmittanceindex exceeding 80%, preferably exceeding 90%.

Thereby, any decorative layer or decorative print is visible through thewear resistant foil. Preferably, the wear resistant foil does notinfluence of the impression of any decorative layer or decorative printarranged beneath the wear resistant foil. The wear resistant foil ispreferably non-pigmented.

The wear resistant particles may be enclosed by the first foil and thesecond thermoplastic material after being adhered to each other. Thewear resistant particles may be encapsulated by the second foil.Preferably, the wear resistant particles do not protrude from a surfaceof a layer formed by the second thermoplastic material after beingadhered to the first layer. If the wear resistant particles protrudebeyond the surface of the layer formed by the second thermoplasticmaterial, the wear resistance foil will cause wear on items placed onthe wear resistance foil. For example, when the wear resistant foil isused a top surface of a flooring, protruding wear resistant particleswill cause wear on socks, shoes, etc. Further, protruding wear resistantparticles would cause a rough and/or harsh surface of the wear resistantfoil, as provided by a slip resistant surface. The aim of the wearresistant particles enclosed by the thermoplastic material is to providewear resistance when the second foil is worn, not to provide slipresistance.

The wear resistant particles and the second thermoplastic material maybe applied as a mix. As an alternative or complement, the wear resistantparticles and the second thermoplastic material may be appliedseparately.

The second thermoplastic material may be applied in molten form. Thesecond thermoplastic material may be applied in an extrusion processsuch as extrusion lamination or extrusion coating on the first foil.

The first thermoplastic material may be or comprise polyvinyl chloride(PVC), polyester (PE), polypropylene (PP), polyethylene (PE),polystyrene (PS), polyurethane (PU), polyethylene terephthalate (PET),polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof.

The second thermoplastic material may be or comprise polyvinyl chloride(PVC) or polyurethane (PU). The second thermoplastic material may be orcomprise polyvinyl chloride (PVC), polyester (PE), polypropylene (PP),polyethylene (PE), polystyrene (PS), polyurethane (PU), polyethyleneterephthalate (PET), polyacrylate, methacrylate, polycarbonate,polyvinyl butyral, polybutylene terephthalate, or a combination thereof.

The first foil may substantially consist of the thermoplastic material,preferably polyvinyl chloride, and optionally additives.

Additives may be plasticizers, stabilizers, lubricants, degassingagents, coupling agents, compatibilizers, crosslinking agents, etc.

The first foil may be a decorative foil. The first foil may be printed,for example by digital printing, direct printing, rotogravure printing,etc.

The second thermoplastic material may be or comprise polyvinyl chloride(PVC) or polyurethane (PU).

By arranging the second thermoplastic material being or comprisingpolyurethane, no additional polyurethane containing coating has to beprovided on top of the wear resistant foil. Thereby, the layeredstructure of a LVT product may be simplified. Furthermore, compared tofor example a conventional wear layer substantially consisting of PVC, awear resistant foil comprising an upper portion of polyurethane (PU)obtains improved chemical resistance. Its scratch resistance andmicro-scratch resistance are also improved. An upper layer ofpolyurethane (PU) also provides improved resistance against black heelmark. An additional advantage is that curable polyurethane, such as UVcurable polyurethane, shrinks when curing. By pressing a thermoplasticpolyurethane (PU) material, no, or at least reduced, such shrinkingoccurs.

In one embodiment, the first thermoplastic material may be or comprisespolyvinyl chloride (PVC) and the second thermoplastic material comprisespolyurethane (PU). Thereby, a wear resistant foil having the propertiesof both polyvinyl chloride (PVC) and polyurethane (PU) is provided.

The wear resistant particles comprise aluminum oxide. The wear resistantmay comprise carborundum, quartz, silica, glass, glass beads, glassspheres, silicon carbide, diamond particles, hard plastics, reinforcedpolymers and organics.

The wear resistant particles may have an average particle size of lessthan 45 μm.

The wear resistant particles may have a refractive index similar to therefractive index of the second thermoplastic material. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

A layer formed by the second thermoplastic material and the wearresistant particles may have a thickness being less than 75 μm, forexample, such as about 50 μm, after being adhered to the first foil, forexample, by pressing.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles. The wear resistant particlesmay have an average particle size being larger than the thickness of thelayer formed by the second thermoplastic material and the wear resistantparticles. However, during pressing, the wear resistant particles arepressed into the first foil such that the wear resistant particles donot protrude beyond an upper surface of the layer formed by the secondthermoplastic material and the wear resistant particles after pressing,although the wear resistant particles having an average particle sizeexceeding the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the second thermoplastic material andthe wear resistant particles may be less than 1.5:1.

The thickness of the layer formed by the second thermoplastic materialand the wear resistant particles may be less than the thickness of thefirst foil.

The method may further comprise applying scratch resistant particles onthe first foil, or together with the second thermoplastic material. Thescratch resistant particles may be or comprise nano-sized silicaparticles, preferably fused silica particles. The scratch resistantparticles may be or comprise aluminum oxide.

According to a second aspect, a method of forming a building panel isprovided. The method comprises applying a wear resistant foil producedaccording to the first aspect on a core, and applying pressure to thewear resistant foil and the core for forming a building panel.

The core may be provided with a decorative layer. The core may beprovided with a print on a surface of the core. The wear resistant foilmay be arranged on the decorative layer, or on the print. Alternatively,the first foil of the wear resistant foil may be a decorative layer.

The core may comprise a third thermoplastic material.

The first, second and third thermoplastic material may be thermoplasticmaterials of different types, or may be the same type of thermoplasticmaterial. The first, second and third thermoplastic material may be orcomprise any one of the follow group: polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The core may be a thermoplasticcore, a WPC (Wood Plastic Composite), etc. The core may be provided withseveral layers. The core may be foamed.

The core may be a wood-based board or a mineral board. The core may inembodiments be HDF, MDF, particleboard, OSB, Wood Plastic Composite(WPC).

The decorative layer may be a thermoplastic foil. The decorative layermay comprise any of the thermoplastic material listed above.

According to a third aspect, a method to produce a building panel isprovided. The method includes providing a core, applying a first foilcomprising a first thermoplastic material on the core, applying wearresistant particles and a second thermoplastic material on the firstfoil, and adhering the core to the first foil to the secondthermoplastic material and the wear resistant particles to each other toform a building panel.

The first and the second thermoplastic material may be thermoplasticmaterials of different type, or may be thermoplastic material of thesame type.

In one embodiment, the wear resistant foil is produced in connectionwith forming the building panel. The wear resistant foil may belaminated together when laminating any other layer, for example adecorative layer, a balancing layer, etc., to the core.

An advantage of at least embodiments of the present disclosure is that awear resistant foil having improved wear resistance is provided. Byincluding wear resistant particles in the wear resistant foil, the wearresistant particles provide additional wear resistance to thethermoplastic materials of the first and the second foil. The wearresistance of the foil is improved compared to a conventional wear layerof LVT products.

Furthermore, conventional coatings, for example a UV curable PU coatingconventionally applied on the wear layer, may be replaced by using thewear resistant foil according to the disclosure instead. A conventionalcoating step may be replaced by arranging a single foil. Thereby, theproduction process is simplified and the number of steps in theproduction process is reduced by arranging a wear resistant foil havingimproved wear resistant properties instead of several layers orcoatings.

By using different thermoplastic material in the first foil and in thesecond thermoplastic material applied on the first foil, it is possibleto benefit from different thermoplastic material having differentproperties. The desired properties of the thermoplastic material of thefirst foil may differ from the desired properties of the secondthermoplastic material applied on the first foil. For the layer formedby the second thermoplastic material and the wear resistant particlesarranged on the first foil, properties such as stain resistance andscratch resistance are important, and the choice of the thermoplasticmaterial can be chosen to match these criteria. Usually, suitablethermoplastic material for forming the layer applied on the first foilmay be more expensive compared to thermoplastic material used as, forexample, in printed film or as core material. By only using suchthermoplastic material in the layer arranged on the first foil, the costof the wear resistant foil can be controlled. Further, the layer formedby the second thermoplastic material can have a layer thickness beingless than a layer thickness of the first foil. By choosing differentthermoplastic materials for the first foil and the overlying layer, thethermoplastic materials can be used in an efficient and cost effectivemanner. By adjusting the layer thicknesses, the materials can be used inan even more efficient manner.

The object of the wear resistant particles is to provide wear resistanceof the foil when being worn, not to provide slip resistance.

The second thermoplastic material may be in powder form when applied onthe first foil.

The wear second thermoplastic material may be in powder form whenadhered to the first foil, such as, for example, when pressed to thefirst foil.

The first foil, the second thermoplastic material and the wear resistantparticles may be adhered to each other by pressing the first foil, thewear resistant particles and the second thermoplastic material together.

The first foil together with the wear resistant particles and the secondthermoplastic material form a wear resistant foil, preferably beingtransparent, or at least substantially transparent, for example, havinga light transmittance index exceeding 80%, preferably exceeding 90%.Thereby, any decorative layer or decorative print is visible through thewear resistant foil. Preferably, the wear resistant foil does notinfluence of the impression of any decorative layer or decorative printarranged beneath the wear resistant foil. The wear resistant foil ispreferably non-pigmented.

The wear resistant particles may be enclosed by the first foil and thesecond thermoplastic material after being adhered to each other.

Preferably, the wear resistant particles do not protrude from a surfaceof a layer formed by the second thermoplastic material opposite thefirst foil after pressing. If the wear resistant particles protrudebeyond the surface of the second thermoplastic material, the wearresistance foil will cause wear on items placed on the wear resistancefoil. For example, when the wear resistant foil is used a top surface ofa flooring, protruding wear resistant particles will cause wear onsocks, shoes, etc. Further, protruding wear resistant particles wouldcause a rough and/or harsh surface of the wear resistant foil, asprovided by a slip resistant surface. The aim of the wear resistantparticles enclosed by the thermoplastic material is to provide wearresistance when the second thermoplastic material is worn, not toprovide slip resistance.

The wear resistant particles and the second thermoplastic material maybe applied as a mix. As an alternative or complement, the wear resistantparticles and the second thermoplastic material may be appliedseparately.

The second thermoplastic material may be applied in molten form. Thesecond thermoplastic material may be applied in an extrusion processsuch as extrusion lamination or extrusion coating on the first foil.

The first thermoplastic material may be or comprise polyvinyl chloride(PVC), polyester (PE), polypropylene (PP), polyethylene (PE),polystyrene (PS), polyurethane (PU), polyethylene terephthalate (PET),polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof.

The second thermoplastic material may be or comprise polyvinyl chloride(PVC) or polyurethane (PU). The second thermoplastic material may be orcomprise polyvinyl chloride (PVC), polyester (PE), polypropylene (PP),polyethylene (PE), polystyrene (PS), polyurethane (PU), polyethyleneterephthalate (PET), polyacrylate, methacrylate, polycarbonate,polyvinyl butyral, polybutylene terephthalate, or a combination thereof.

In one embodiment, the first thermoplastic material comprises polyvinylchloride (PVC) and the second thermoplastic material comprisespolyurethane (PU).

The wear resistant particles may preferably comprise aluminum oxide. Thewear resistant particles may comprise aluminum oxide such as corundum,carborundum, quartz, silica, glass, glass beads, glass spheres, siliconcarbide, diamond particles, hard plastics, reinforced polymers andorganics, or combinations thereof.

The wear resistant particles may have an average particle size of lessthan 45 μm. The wear resistant particles may have a refractive indexsimilar to the refractive index of the second thermoplastic material.The wear resistant particles may have a refractive index of 1.4-1.7. Inone embodiment, the wear resistant particle may have a refractive indexof 1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractiveindex of the wear resistant particles may not differ from the refractiveindex of the second thermoplastic material more than ±20%.

A layer formed by the second thermoplastic material and the wearresistant particles may have a thickness being less than 75 μm, forexample, such as about 50 μm, after being adhered to each other.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles. The wear resistant particlesmay have an average particle size being larger than the thickness of thelayer formed by the second thermoplastic material and the wear resistantparticles. However, during pressing, the wear resistant particles arepressed into the first foil such that the wear resistant particles donot protrude beyond an upper surface of the layer formed by the secondthermoplastic material and the wear resistant particles after pressing,although the wear resistant particles having an average particle sizeexceeding the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the second thermoplastic material andthe wear resistant particles may be less than 1.5:1.

The thickness of the layer formed by the second thermoplastic materialand the wear resistant particles may be less than the thickness of thefirst foil.

The method may further comprise applying scratch resistant particles onthe first foil. Alternatively, or as a complement, the scratch particlesmay be applied together with the second thermoplastic material. Thescratch resistant particles may be or comprise nano-sized silicaparticles, preferably fused silica particles. The scratch resistantparticles may be or comprise aluminum oxide.

The core may comprise a third thermoplastic material.

The first, second and third thermoplastic material may be thermoplasticmaterials of different types, or may be the same type of thermoplasticmaterial.

The third thermoplastic material may be or comprise polyvinyl chloride(PVC), polyester, polypropylene (PP), polyethylene (PE), polystyrene(PS), polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The core may be a thermoplasticcore, a WPC (Wood Plastic Composite), etc. The core may be provided withseveral layers. The core may be foamed.

The core may be a wood-based board or a mineral board. The core may inembodiments be HDF, MDF, particleboard, OSB, Wood Plastic Composite(WPC).

A decorative layer may be arranged on the core. In one embodiment, themethod may comprise applying a decorative layer prior to applying thefirst foil. The decorative layer may be a thermoplastic layer. Thedecorative layer may be a wood powder layer comprising a thermosettingbinder and lignocellulosic or cellulosic particles. The decorative layermay be a thermoplastic layer applied as a powder, preferably comprisinga print printed into the thermoplastic material in powder form. Thedecorative layer may be a wood veneer layer, a cork layer or adecorative paper.

In one embodiment, the first foil is arranged directly on the core. Thecore may be provided with a print, and the first foil is arranged on theprint. Alternatively, or as a complement, the first foil may be adecorative foil. The first foil may be printed, for example by digitalprinting, direct printing, rotogravure, etc. Preferably, the print isprovided on a surface of the first foil facing the core.

The method may further comprise applying a coating on the wear resistantfoil. The coating may comprise acrylate or methacrylate monomer oracrylate or methacrylate oligomer. The coating may be radiation curing,such as UV curing or electron beam curing.

According a fourth aspect, a method to produce a wear resistant foil isprovided. The method comprises providing a carrier, applying wearresistant particles and a second thermoplastic material on the carrier,and adhering the wear resistant particles and the second thermoplasticmaterial to each other to form a wear resistant foil.

Embodiments of the fourth aspect all the advantages of the first aspect,which previously has been discussed, whereby the previous discussion isapplicable also for the building panel.

The second thermoplastic material may be in powder form when applied onthe carrier.

The wear second thermoplastic material may be in powder form whenadhered to the carrier, such as, for example, when pressed to thecarrier.

The first foil, the second thermoplastic material and the wear resistantparticles may be adhered to each other by pressing the first foil, thewear resistant particles and the second thermoplastic material together.

The wear resistant foil is preferably transparent, or at leastsubstantially transparent, for example, having a light transmittanceindex exceeding 80%, preferably exceeding 90%. Thereby, any decorativelayer or decorative print is visible through the wear resistant foil.Preferably, the wear resistant foil does not influence of the impressionof any decorative layer or decorative print arranged beneath the wearresistant foil. The wear resistant foil is preferably non-pigmented.

The wear resistant particles may be enclosed by the first foil and thesecond thermoplastic material after being adhered to each other.

Preferably, the wear resistant particles do not protrude from a surfaceof a layer formed by the second thermoplastic material after beingadhered to the first foil. If the wear resistant particles protrudebeyond the surface of the layer formed by the second thermoplasticmaterial, the wear resistance foil will cause wear on items placed onthe wear resistance foil. For example, when the wear resistant foil isused a top surface of a flooring, protruding wear resistant particleswill cause wear on socks, shoes, etc. Further, protruding wear resistantparticles would cause a rough and/or harsh surface of the wear resistantfoil, as provided by a slip resistant surface. The aim of the wearresistant particles enclosed by the second thermoplastic material is toprovide wear resistance when the second foil is worn, not to provideslip resistance.

The wear resistant particles and the second thermoplastic material maybe applied as a mix. As an alternative or complement, the wear resistantparticles and the second thermoplastic material may be appliedseparately.

The second thermoplastic material may be applied in molten form. Thesecond thermoplastic material may be applied in an extrusion processsuch as extrusion lamination or extrusion coating on the carrier.

In one embodiment, the carrier may be a first foil comprising a firstthermoplastic material as discussed above in respect of the thirdaspect.

The carrier may be a substrate.

In one embodiment, the carrier may be a temporary carrier such as arelease foil or conveyor means.

In one embodiment, the carrier may be a core. The core may be athermoplastic core, a Wood Plastic Composite (WPC), a wood-based boardor a mineral board. The step of adhering may comprise adhering thecarrier to the second thermoplastic material and the wear resistantparticles.

The second thermoplastic material may be or comprise polyvinyl chloride(PVC) or polyurethane (PU).

The method may further comprise releasing the wear resistant foil fromthe carrier. The wear resistant particles may comprise aluminum oxide.The wear resistant may comprise carborundum, quartz, silica, glass,glass beads, glass spheres, silicon carbide, diamond particles, hardplastics, reinforced polymers and organics.

The wear resistant particles may have an average particle size of lessthan 45 μm.

The wear resistant particles may have a refractive index similar to therefractive index of the second thermoplastic material. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

A layer formed by the second thermoplastic material and the wearresistant particles may have a thickness being less than 75 μm, forexample, such as about 50 μm, after being adhered to each other.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles. The wear resistant particlesmay have an average particle size being larger than the thickness of thelayer formed by the second thermoplastic material and the wear resistantparticles. However, during pressing, the wear resistant particles arepressed into the carrier such that the wear resistant particles do notprotrude beyond an upper surface of the layer formed by the secondthermoplastic material and the wear resistant particles after pressing,although the wear resistant particles having an average particle sizeexceeding the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the second thermoplastic material andthe wear resistant particles may be less than 1.5:1.

According a fifth aspect, a building panel is provided. The buildingpanel comprises a core, a wear resistant foil arranged on a surface ofthe core, wherein the wear resistant foil comprises a secondthermoplastic material and wear resistant particles substantiallyhomogenously distributed in said second thermoplastic material.

Embodiments of the fifth aspect incorporate all the advantages of thefirst, which previously has been discussed, whereby the previousdiscussion is applicable also for the building panel.

The wear resistant foil is preferably transparent, or at leastsubstantially transparent, for example, having a light transmittanceindex exceeding 80%, preferably exceeding 90%. Thereby, any decorativelayer or decorative print is visible through the wear resistant foil.Preferably, the wear resistant foil does not influence of the impressionof any decorative layer or decorative print arranged beneath the wearresistant foil. The wear resistant foil is preferably non-pigmented.

The wear resistant particles may be enclosed by the second thermoplasticmaterial.

Preferably, the wear resistant particles do not protrude from a surfaceof a layer formed by the second thermoplastic material. If the wearresistant particles protrude beyond the surface of the second foil, thewear resistance foil will cause wear on items placed on the wearresistance foil. For example, when the wear resistant foil is used a topsurface of a flooring, protruding wear resistant particles will causewear on socks, shoes, etc. Further, protruding wear resistant particleswould cause a rough and/or harsh surface of the wear resistant foil, asprovided by a slip resistant surface. The aim of the wear resistantparticles enclosed by the thermoplastic material is to provide wearresistance when the second foil is worn, not to provide slip resistance.

The wear resistant foil may further comprise a first foil comprising afirst thermoplastic material.

The first thermoplastic material may be or comprise polyvinyl chloride(PVC). The first thermoplastic material may be or comprise polyvinylchloride (PVC), polyester (PE), polypropylene (PP), polyethylene (PE),polystyrene (PS), polyurethane (PU), polyethylene terephthalate (PET),polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof.

The second thermoplastic material may be or comprise polyvinyl chloride(PVC) or polyurethane (PU). The second thermoplastic material may be orcomprise polyvinyl chloride (PVC), polyester (PE), polypropylene (PP),polyethylene (PE), polystyrene (PS), polyurethane (PU), polyethyleneterephthalate (PET), polyacrylate, methacrylate, polycarbonate,polyvinyl butyral, polybutylene terephthalate, or a combination thereof.

The wear resistant particles may preferably comprise aluminum oxide. Thewear resistant particles may comprise aluminum oxide, carborundum,quartz, silica, glass, glass beads, glass spheres, silicon carbide,diamond particles, hard plastics, reinforced polymers and organics, or acombination thereof.

The wear resistant particles may have an average particle size of lessthan 45 μm.

The wear resistant particles may have a refractive index similar to therefractive index of the second thermoplastic material. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

A layer formed by the second thermoplastic material and the wearresistant particles may have a thickness being less than 75 μm, forexample, such as about 50 μm, after being adhered.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the second thermoplasticmaterial and the wear resistant particles. The wear resistant particlesmay have an average particle size being larger than the thickness of thelayer formed by the second thermoplastic material and the wear resistantparticles. However, during pressing, the wear resistant particles arepressed into the core or any intermediate layer such as a first foilsuch that the wear resistant particles do not protrude beyond an uppersurface of the layer formed by the second thermoplastic material and thewear resistant particles after pressing, although the wear resistantparticles having an average particle size exceeding the thickness of thelayer formed by the second thermoplastic material and the wear resistantparticles.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the second thermoplastic material andthe wear resistant particles may be less than 1.5:1.

The thickness of the layer formed by the second thermoplastic materialand the wear resistant particles may be less than the thickness of thefirst foil.

The building panel may further comprise a decorative layer arranged onthe core, wherein the wear resistant foil is arranged on the decorativelayer.

The core may comprise a third thermoplastic material. The thirdthermoplastic material may be or comprise polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof.

The core may be a thermoplastic core, a Wood Plastic Composite (WPC), awood-based board or a mineral board.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will by way of example be described in moredetail with reference to the appended schematic drawings, which showembodiments of the present disclosure.

FIG. 1 shows a method to produce a wear resistant foil according a firstembodiment.

FIG. 2 shows a method to produce a wear resistant foil according to asecond embodiment.

FIG. 3 shows a building panel.

FIG. 4 shows a method to produce a building panel.

FIGS. 5A-B show embodiments of a building panel.

FIG. 6A shows a method to produce a wear resistant foil.

FIG. 6B shows a method to produce a building panel.

DETAILED DESCRIPTION

A method to produce a wear resistant foil 10 according to an embodimentwill now be described with reference to FIG. 1. FIG. 1 shows aproduction line for producing a wear resistant foil 10.

The first foil 1 comprises a first thermoplastic material. The firstthermoplastic material may be polyvinyl chloride (PVC), polyester,polypropylene (PP), polyethylene (PE), polystyrene (PS), polyurethane(PU), polyethylene terephthalate (PET), polyacrylate, methacrylate,polycarbonate, polyvinyl butyral, polybutylene terephthalate, or acombination thereof.

In FIG. 1, the first foil 1 is provided as a continuous web. In otherembodiments, the first foil 1 may also be cut into sheets. The firstfoil 1 may also be formed by an extrusion process. The first foil 1 mayalso be formed of a powder layer comprising the first thermoplasticmaterial in powder form.

Preferably, the first foil 1 is formed of the thermoplastic material.The first foil 1 may substantially consist of the thermoplasticmaterial, and optionally additives. Additives may be plasticizers,stabilizers, lubricants, degassing agents, coupling agents,compatibilizers, crosslinking agents, etc.

In one embodiment, the first foil 1 is a PVC foil.

The first foil 1 may have a thickness of 0.1-1 mm.

In one embodiment, the first foil 1 is a decorative foil. The first foil1 may be printed, for example by digital printing, direct printing,rotogravure, etc.

As shown in FIG. 1, an applying device 3 applies, preferably scatters, asecond thermoplastic material 5 in powder form and wear resistantparticles 4 on the first foil 1. In FIG. 1, the thermoplastic material 5and the wear resistant particles 4 are applied as a mix.

The thermoplastic material 5 and the wear resistant particles 4 may alsobe applied separately. Preferably, if applied separately, the wearresistant particles 4 are applied first, and the second thermoplasticmaterial 5 is applied on the wear resistant particles 4.

The second thermoplastic material 5 may be the same as in the first foil1, or being different from the thermoplastic material of the first foil1. The second thermoplastic material 5 may be polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof.

In the embodiment shown in FIG. 1, the second thermoplastic material 5is applied as a powder. By powder is also meant powder that has formedgranules of the thermoplastic material, dry blends of the thermoplasticmaterial, or agglomerates of the thermoplastic material. The granulesmay comprise both the thermoplastic material 5 and the wear resistantparticles 4. The agglomerates may comprise both the thermoplasticmaterial 5 and the wear resistant particles 4.

The average particle size of the thermoplastic material 5 may be lessthan 500 μm, preferably 50-250 μm. The thermoplastic material 5 in a dryblend may have size of less than 500 μm. Granules of the thermoplasticmaterial 5 may have an average particle size of 200-4000 μm, preferablyless than 1000 μm.

In the embodiment shown in FIG. 1, the wear resistant particles 4 andthe second thermoplastic material 5 is applied as a mix.

In embodiments, the second thermoplastic material 5 may be applied inmolten form, which is described in more detail with reference to FIG.6A. The wear resistant particles 4 may be mixed with the secondthermoplastic material 5 in molten form or applied separately. Thesecond thermoplastic 5 in molten form may be applied in an extrusionprocess such as extrusion lamination and extrusion coating on the firstfoil 1.

The wear resistant particles 4 may be aluminum oxide particles such ascorundum. Alternatively, or as a complement, the wear resistantparticles 4 may be carborundum, quartz, silica, glass, glass beads,glass spheres, silicon carbide, diamond particles, hard plastics,reinforced polymers and organics.

The wear resistant particles 4 preferably have an average particle sizewithin the range of 10-200 μm, preferably within the range of 50-120 μmsuch as 50-100 μm. The wear resistant particles 4 may have an averageparticle size of less than 50 μm, preferably less than 45 μm. The wearresistant particles 4 may have a spherical shape or an irregular shape.The wear resistant particles 4 may be surface treated. The wearresistant particles 4 may be silane-treated particles.

The wear resistant particles 4 may have a refractive index similar tothe refractive index of the second thermoplastic material 5. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

The wear resistant particles may be applied in an amount of 20-100 g/m2,preferably in an amount of 40-60 g/m2.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing. However,the wear resistant particles may have an average particle size beinglarger than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material 5 after pressing. Duringpressing, the wear resistant particles are pressed into the first foilsuch that the wear resistant particles do not protrude beyond an uppersurface of the layer formed by the second thermoplastic material 5,although the wear resistant particles having an average particle sizeexceeding the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the wear resistant particles and thesecond thermoplastic material after pressing may be less than 1.5:1.

Scratch resistant particles (not shown) may also be applied on the firstfoil 1, as a mix together with the thermoplastic material 5 and the wearresistant particles 4 or separately. By scratch resistant particles aremeant particles improving the scratch or scratch resistant properties ofthe foil. The scratch resistant particles may be applied together withthe wear resistant particles 4, for example as a mix, or may be appliedseparately. Preferably, the scratch particles are arranged on an upperpart of the layer formed by the thermoplastic material 5 and the wearresistant particles 4. The scratch resistant particles may be may be orcomprise nano-sized silica particles, preferably fused silica particles.The scratch resistant particles may be or comprise aluminum oxide.

The scratch resistant particles may be disc shaped particles, preferablyhaving a width/thickness ratio being equal or exceeding 3:1, morepreferably being equal or exceeding 5:1. Such disc-shaped particlesorientate along the surface of the foil, thereby improving the scratchresistance of the foil. The scratch resistant particles may have anaverage particle size of 1-50 μm, preferably 10-20 μm.

Additives may also be applied on the first foil 1, or together with thesecond thermoplastic material. Additives may be plasticizers,stabilizers, lubricants, degassing agents, coupling agents,compatibilizers, crosslinking agents, etc.

In one embodiment, the first foil 1 is a PVC foil and the secondthermoplastic material 5 is polyurethane (PU) in powder form. In oneembodiment, the first foil 1 is a PVC foil and the second thermoplasticmaterial 5 is PVC in powder form.

The first foil 1 and the second thermoplastic material 5 in powder formare thereafter adhered to each other, for example, being pressedtogether, to form a wear resistant foil 10 comprising the first foil 1,the second thermoplastic material 5 and the wear resistant particles 4.

The first foil 1 and the second thermoplastic material 5 in powder formmay be pressed together in a calendering process. As shown in FIG. 1,the first foil 1 and the second thermoplastic material 5 in powder formare pressed together in continuous press 6. The first and secondthermoplastic material may be adhered together by pressure alone, byheat and pressure, by pressure and adhesive, or by heat, pressure, andadhesive.

Preferably, both pressure and heat is applied in order to adhere thefirst foil and the second thermoplastic material together. Asalternative or complements to a calendering process, a continuous orstatic press may also be used. The pressing operation may for example bemade as a hot-hot process, a hot-cold process, etc. The pressing may bemade with an embossed press matrix or press roller, such that anembossed structure is formed in the wear resistant foil.

Depending on the thermoplastic materials and process used, the pressureapplied may be 5-100 bar, applied for example during 5-500 seconds. Thetemperature may be 80-300° C., such as 100-250° C., such as 150-200° C.

By the process described above with reference to FIG. 1, a wearresistant foil 10 is formed. The wear resistant foil 10 may be formed asa continuous foil, or be cut into sheets. The second thermoplasticmaterial 5 and the wear resistant particles 4 form an upper part of thewear resistant foil 10. Preferably, the wear resistant particles 4 maybe substantially homogenous distributed in the upper part of the wearresistant foil 10. The first foil 1 forms a lower part of the wearresistant foil 10. As seen in a cross-section of the wear resistantfoil, the wear resistant particles 4 are heterogeneously distributedthrough the wear resistant foil 10. There is a higher concentration ofthe wear resistant particles 4 in the upper parts of the wear resistantfoil 10 than in the lower parts of the wear resistant foil 10.

After adhering the layers, the wear resistant particles are enclosed bythe first foil and the second thermoplastic material. Although the wearresistant particles and the second thermoplastic material may be appliedas mix, during the pressing, the second thermoplastic material fuses andencloses the wear resistant particles. Preferably, the wear resistantparticles do not protrude beyond the surface of the layer formed thesecond thermoplastic material facing away from the first foil. Thereby,a wear resistant foil having a smooth surface can be formed.

The wear resistant foil 10 is preferably transparent, or substantiallytransparent.

The second thermoplastic material 5 and the wear resistant particles 4may be formed into a layer, which may have a thickness of 0.01-1 mm,preferably as measured in the final product, for example, after pressingor extruding. Preferably, the layer formed by the second thermoplasticmaterial 5 and the wear resistant particles 4 has a thickness less than0.5 mm, more preferably less than 75 μm such as about 50 μm, preferablyas measured in the final product, for example, after pressing orextruding.

Different additives may be included to the first foil 1 compared to thesecond thermoplastic material 5 in powder form in order to obtaindifferent properties in different layers of the wear resistant foil 10.

A wear resistant foil 10′ may also be produced in accordance with theembodiment described with reference to FIG. 2. In the embodiment shownin FIG. 2, a second thermoplastic material 5 in powder form and wearresistant particles 4 are applied, preferably scattered, by an applyingdevice 3 on a carrier 7. The carrier 7 may be a substrate. The carrier 7may for example be a release foil or Teflon® treated press plate. It isalso contemplated that the carrier 7 may be a core 21, for example,provided with a print. The core 21 may a thermoplastic core, a WPC (WoodPlastic Composite), a wood-based board such as HDF or MDF, a mineralboard, etc. It is also contemplated that a first thermoplastic materialin powder form may be applied on the carrier.

The second thermoplastic material 5 may be polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof.

By powder is also meant powder that has formed granules of thethermoplastic material 5, dry blends of the thermoplastic material 5, oragglomerates of the thermoplastic material 5. The granules may compriseboth the thermoplastic material 5 and the wear resistant particles 4.The agglomerates may comprise both the thermoplastic material 5 and thewear resistant particles 4.

The average particle size of the thermoplastic material 5 may be lessthan 500 μm, preferably 50-250 μm. The thermoplastic material 5 in a dryblend may have size of less than 500 μm. Granules of the thermoplasticmaterial 5 may have an average particle size of 200-4000 μm, preferablyless than 1000 μm.

A layer of the second thermoplastic material 5 is applied on the carrier7. Preferably, the second thermoplastic material 5 and the wearresistant particles 4 are applied as a mix. The second thermoplasticmaterial 5 and the wear resistant particles 4 may also be appliedseparately. Preferably, if applied separately, the wear resistantparticles 4 are applied first, and the second thermoplastic material 5is applied on the wear resistant particles 4.

In the embodiment shown in FIG. 2, the second thermoplastic material 5is applied in powder form. In embodiments, the second thermoplasticmaterial 5 may be applied in molten form, which is described in moredetail with reference to FIG. 6A. The wear resistant particles 4 may bemixed with the second thermoplastic material 5 in molten form or appliedseparately. The second thermoplastic 5 in molten form may be applied inan extrusion process such as extrusion lamination and extrusion coatingon the carrier 7.

More than one type of thermoplastic material 5 may be applied on thecarrier 7. Thermoplastic materials having different properties may beapplied. As an example, a PVC powder may be applied, and a PU powder maybe applied on the PVC powder for forming a wear resistant foil 10′having different properties. The wear resistant particles 4 may beapplied in between the PVC powder and the PU powder. Different types ofadditives may also be added to the different thermoplastic materials inorder to form a wear resistant foil 10′ having different properties indifferent layers.

The wear resistant particles 4 may be aluminum oxide particles such ascorundum. Alternatively, or as a complement, the wear resistantparticles 4 may be carborundum, quartz, silica, glass, glass beads,glass spheres, silicon carbide, diamond particles, hard plastics,reinforced polymers and organics, or a combination thereof.

The wear resistant particles 4 preferably have an average particle sizewithin the range of 10-200 μm, preferably within the range of 50-120 μm,such as 50-100 μm. The wear resistant particles 4 preferably have anaverage particle size of less than 50 μm, preferably less than 45 μm.The wear resistant particles 4 may have a spherical shape or anirregular shape. The wear resistant particles 4 may be surface treated.The wear resistant particles 4 may be silane-treated particles.

The wear resistant particles 4 may have a refractive index similar tothe refractive index of the second thermoplastic material 5. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

The wear resistant particles may be applied in an amount of 20-100 g/m2,preferably in an amount of 40-60 g/m2.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing. However,the wear resistant particles may have an average particle size beinglarger than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing. Duringpressing, the wear resistant particles are pressed into the carrier suchthat the wear resistant particles do not protrude beyond an uppersurface of the layer, although the wear resistant particles have anaverage particle size exceeding the thickness of the layer formed by thewear resistant particles and the second thermoplastic material afterpressing.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the wear resistant particles and thesecond thermoplastic material after pressing may be less than 1.5:1.

Scratch resistant particles (not shown) may also be applied on thecarrier 7, or as a mix together with the thermoplastic material 5 andthe wear resistant particles 4 or separately. By scratch resistantparticles are meant particles improving the scratch or scratch resistantproperties of the foil. The scratch resistant particles may be appliedtogether with the wear resistant particles 4, for example as a mix, ormay be applied separately. Preferably, the scratch particles arearranged on an upper part of the layer formed by the thermoplasticmaterial 5 and the wear resistant particles 4. The scratch resistantparticles may be may be or comprise nano-sized silica particles,preferably fused silica particles. The scratch resistant particles maybe or comprise aluminum oxide.

The scratch resistant particles may be disc shaped particles, preferablyhaving a width/thickness ratio being equal or exceeding 3:1, morepreferably being equal or exceeding 5:1. Such disc-shaped particlesorientate along the surface of the foil, thereby improving the scratchresistance of the foil. The scratch resistant particles may have anaverage particle size of 1-50 μm, preferably 10-20 μm.

Additives may also be applied on the carrier 7. Additives may beplasticizers, stabilizers, lubricants, degassing agents, couplingagents, compatibilizers, crosslinking agents, etc.

The additives may also be applied together with the second thermoplasticmaterial 5.

The second thermoplastic material 5 in powder form and the wearresistant particles 4 are thereafter adhered to each other such as fusedtogether, preferably pressed together to form a wear resistant foil 10′.

The second thermoplastic material 5 in powder form and the wearresistant particles 4 may be pressed together in a calendering process.As shown in FIG. 2, the second thermoplastic material 5 and the wearresistant particles 4 are pressed together in a continuous press 6.Preferably, both pressure and heat is applied in order to form a wearresistant foil 10′ of the second thermoplastic material 5 and the wearresistant particles 4. As alternative or complements to a calendaringprocess, a continuous or static press may also be used. The pressing mayfor example be made as a hot-hot process, a hot-cold process, etc. Thepressing may be made with an embossed press matrix or press roller, suchthat an embossed structure is formed in the wear resistant foil 10′. Asdescribed above, the second thermoplastic material 5 may also beextruded on the carrier 7, such as extrusion coated or extrusionlaminated to the carrier.

Depending on the thermoplastic materials and process used, the pressureapplied may be 5-100 bar, applied for example during 5-500 seconds. Thetemperature may be 80-300° C., such as 100-250° C., such as 150-200° C.

By the process described above with reference to FIG. 2, a wearresistant foil 10′ is formed, comprising the second thermoplasticmaterial and the wear resistant particles. The wear resistant foil 10′is preferably transparent, or substantially transparent.

The wear resistant foil may have a thickness of 0.01-1 mm, preferably asmeasured in the final product, for example, after pressing or extruding.Preferably, the wear resistant foil has a thickness less than 0.5 mm,more preferably less than 0.1 mm, preferably as measured in the finalproduct, for example, after pressing or extruding.

After adhering the layers, the wear resistant particles are enclosed bythe first foil and the second thermoplastic material. Although the wearresistant particles and the second thermoplastic material may be appliedas mix, during the pressing, the second thermoplastic material fuses andencloses the wear resistant particles. Preferably, the wear resistantparticles do not protrude beyond the surface of the layer formed thesecond thermoplastic material facing away from the first foil. Thereby,a wear resistant foil having a smooth surface can be formed.

The wear resistant foil 10, 10′ produced accordance with the embodimentsdescribed when referring to FIG. 1 and FIG. 2, may in a subsequent stepbe adhered to a core 21 to form a building panel 20, as shown in FIG. 3.The building panel 20 may be a floor panel, a wall panel, a ceilingpanel, a furniture component, etc.

The core 21 may comprise a third thermoplastic material. The thirdthermoplastic material may be the same as the first and/or secondmaterial, or be different from the first and/or the second material.

The third thermoplastic material may comprise polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The core may be formed ofseveral layers. The core may be foamed.

In one embodiment, the core 21 comprises the third thermoplasticmaterial and fillers. The fillers may comprise calcium carbonate, suchas chalk and/or limestone, or sand.

In one embodiment, the core 21 is a Wood Plastic Composite (WPC),comprising the third thermoplastic material and wood particles asfillers.

The core 21 may be provided with a decorative layer 22 arranged on a topsurface of the core 21, as shown in FIG. 3. The wear resistant foil 10,10′ is then arranged on the decorative layer 22. The decorative layer 22may be a decorative foil comprising a thermoplastic material. Thethermoplastic material of the decorative layer may be or comprisepolyvinyl chloride (PVC), polyester, polypropylene (PP), polyethylene(PE), polystyrene (PS), polyurethane (PU), polyethylene terephthalate(PET), polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof. The decorativelayer 22 is preferably printed, for example by direct printing,rotogravure, or digital printing.

The core 21 may also be provided with a balancing layer (not shown)arranged on a lower surface of the core 21, opposite the decorativelayer 22. Any intermediate layer may also be arranged between the core21 and the decorative layer 22.

The wear resistant foil 10, 10′ produced according to the methoddescribed above with reference to FIG. 1 or FIG. 2, is arranged on thedecorative layer. The core 21, the decorative layer 22, and the wearresistant foil 10, 10′ are pressed together to form a building panel 20.Heat may also be applied when applying pressure. The core, thedecorative layer and the wear resistant foil may be pressed together ina continuous or static press, or in a calendering operation. Asalternatively, the wear resistant foil 10, 10′, optionally comprisingthe decorative layer 22, may be adhered to the core 21 by an adhesive,such as hot melt.

The wear resistant foil 10, 10′ is preferably transparent, orsubstantially transparent, for example, having a light transmittanceindex exceeding 80%, preferably exceeding 90%.

A coating (not shown) may be applied on the wear resistant foil 10, 10′.The coating may comprise acrylate or methacrylate monomer or acrylate ormethacrylate oligomer. The coating may be radiation curing, such as UVcuring or electron beam curing.

As an alternative to a separate decorative layer 22, a print may beprinted directly on the top surface of core 21. The wear resistant foil10, 10′ is thereby arranged directly on the core 21.

In one embodiment, when the wear resistant foil 10 is produced accordingto the embodiment described with reference to FIG. 1, the first foil 1forms a decorative layer. A separate decorative layer 22 may then beexcluded. The first foil 1 may be printed, for example by digitalprinting, direct printing, rotogravure, etc. Preferably, the print isprovided on side of the first foil 1 adapted to face the core 21. Thewear resistant foil 10 is in this embodiment arranged directly on thecore 21 of the above described type.

An embodiment of the building panel 20 comprises a core 21 comprisingPVC, a decorative foil 22 comprising PVC, a wear resistant foil 10comprising PVC in the first foil 1 and PU applied as the secondthermoplastic material 5.

In other embodiments, the core 21 may be a wood-based board or a mineralboard. The core may, for example, be a HDF, MDF, particleboard, plywood,OSB, etc.

As an alternative to the decorative foil, the decorative layer 22 may beformed of a thermoplastic material applied as a powder on the core. Aprint may be printed in the powder thermoplastic material. Thethermoplastic material in powder form may be polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The wear resistant foil 10, 10′is arranged on the powder layer and pressed together. The core 21 may beof the above described type.

Another alternative to the decorative foil is to apply a thermosettingbinder, preferably an amino resin and in powder form, andlignocellulosic or cellulosic particles for forming the decorative layer22 on the core 21. A print is may be printed in the powder layer, orpigments may be included. The core may be of the above described type.The wear resistant foil 10, 10′ is arranged on the powder layer andpressed together under heat, such that the thermosetting binder of thedecorative layer is cured.

Another alternatives for forming the decorative layer 22 are providing aveneer layer, such as a wood veneer layer or a cork veneer layer or apaper layer for forming the decorative layer.

The different layers, i.e., the core 21, the decorative layer 22, thewear resistant foil 10, 10′, may be provided as continuous layers orbeing cut into sheets for the embodiment described with reference toFIG. 3.

FIG. 4 shows a method to produce a building panel 20 including forming awear resistant foil 10 integrated into the production of the buildingpanel 20. The building panel 20 may be a floor panel, a wall panel, aceiling panel, a furniture component, etc.

A core 21 is provided. The core 21 may comprise a third thermoplasticmaterial. The third thermoplastic material may be the same as the firstand/or second material, or be different from the first and/or the secondmaterial.

The third thermoplastic material may comprise polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The core 21 may be formed ofseveral layers. The core may be foamed.

In one embodiment, the core 21 comprises the third thermoplasticmaterial and fillers. The fillers may comprise calcium carbonate, suchas chalk and/or limestone, or sand. In one embodiment, the core 21 is aWood Plastic Composite (WPC), comprising the third thermoplasticmaterial and wood particles as fillers.

The core 21 may be provided with a decorative layer 22 arranged on a topsurface of the core 21. The wear resistant foil 10 is then arranged onthe decorative surface 22. The decorative layer 22 may be a decorativefoil comprising a thermoplastic material. The thermoplastic material ofthe decorative layer may be or comprise polyvinyl chloride (PVC),polyester, polypropylene (PP), polyethylene (PE), polystyrene (PS),polyurethane (PU), polyethylene terephthalate (PET), polyacrylate,methacrylate, polycarbonate, polyvinyl butyral, polybutyleneterephthalate, or a combination thereof. The decorative layer 22 ispreferably printed, for example by direct printing, rotogravure, ordigital printing.

The core 21 may also be provided with a balancing layer (not shown)arranged on a lower surface of the core 21, opposite the decorativelayer 22. Any intermediate layer or layers may be arranged between thecore 21 and the decorative layer 22.

A first foil 1 is arranged on the core 12. The first foil 1 comprises afirst thermoplastic material. The first thermoplastic material may bepolyvinyl chloride (PVC), polyester, polypropylene (PP), polyethylene(PE), polystyrene (PS), polyurethane (PU), polyethylene terephthalate(PET), polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof.

A first foil 1 is provided, preferably as a continuous web. The firstfoil 1 may also be cut into sheets. The first foil 1 may also be formedby an extrusion process in connection with producing the building panel.The first foil 1 may also be formed of a powder layer comprising thefirst thermoplastic material in powder form.

Preferably, the first foil 1 is formed of the thermoplastic material.The first foil may substantially consist of the thermoplastic material,and optionally additives. Additives may be plasticizers, stabilizers,lubricants, degassing agents, coupling agents, compatibilizers,crosslinking agents, etc.

In one embodiment, the first foil 1 is a PVC foil.

The first foil 1 may have a thickness of 0.1-1 mm.

As shown in FIG. 4, an applying device 3 applies, preferably scatters, asecond thermoplastic material 5 in powder form and wear resistantparticles 4 on the first foil 1. In FIG. 1, the second thermoplasticmaterial 5 and the wear resistant particles 4 are applied as a mix. Thethermoplastic material 5 and the wear resistant particles 4 may also beapplied separately. Preferably, if applied separately, the wearresistant particles 4 are applied first and the second thermoplasticmaterial 5 is applied on the wear resistant particles 4.

The second thermoplastic material 5 may be the same as in the first foil1, or being different from the thermoplastic material of the first foil1. The second thermoplastic may be polyvinyl chloride (PVC), polyester,polypropylene (PP), polyethylene (PE), polystyrene (PS), polyurethane(PU), polyethylene terephthalate (PET), polyacrylate, methacrylate,polycarbonate, polyvinyl butyral, polybutylene terephthalate, or acombination thereof.

In the embodiment shown in FIG. 4, the second material 5 is applied as apowder. By powder is also meant powder that has formed granules of thethermoplastic material 5, dry blends of the thermoplastic material 5, oragglomerates of the thermoplastic material 5. The granules may compriseboth the thermoplastic material 5 and the wear resistant particles 4.The agglomerates may comprise both the thermoplastic material 5 and thewear resistant particles 4.

The average particle size of the thermoplastic material 5 may be lessthan 500 μm, preferably 50-250 μm. The thermoplastic material 5 in a dryblend may have size of less than 500 μm. Granules of the thermoplasticmaterial 5 may have an average particle size of 200-4000 μm, preferablyless than 1000 μm.

In the embodiment shown in FIG. 4, the wear resistant particles 4 andthe second thermoplastic material is applied as a mix.

In the embodiment shown in FIG. 4, the second thermoplastic material 5is applied in powder form. In embodiments, the second thermoplasticmaterial 5 may be applied in molten form, which is described in moredetail with reference to FIG. 6B. The wear resistant particles 4 may bemixed with the second thermoplastic material 5 in molten form or appliedseparately. The second thermoplastic 5 in molten form may be applied inan extrusion process such as extrusion lamination and extrusion coatingon the first foil 1.

The wear resistant particles 4 may be aluminum oxide particles such ascorundum. Alternatively, or as a complement, the wear resistantparticles 4 may be carborundum, quartz, silica, glass, glass beads,glass spheres, silicon carbide, diamond particles, hard plastics,reinforced polymers and organics, or a combination thereof.

The wear resistant particles 4 preferably have an average particle sizewithin the range of 10-200 μm, preferably within the range of 50-120 μm,such as 50-100 μm. The wear resistant particles 4 may have an averageparticle size of less than 50 μm, preferably less than 45 μm. The wearresistant particles 4 may have a spherical shape or an irregular shape.The wear resistant particles 4 may be surface treated. The wearresistant particles 4 may be silane-treated particles.

The wear resistant particles 4 may have a refractive index similar tothe refractive index of the second thermoplastic material 5. The wearresistant particles may have a refractive index of 1.4-1.7. In oneembodiment, the wear resistant particle may have a refractive index of1.4-1.9, preferably 1.5-1.8, for example, 1.7-1.8. The refractive indexof the wear resistant particles may not differ from the refractive indexof the second thermoplastic material more than ±20%.

The wear resistant particles may be applied in an amount of 20-100 g/m2,preferably in an amount of 40-60 g/m2.

The wear resistant particles may have an average particle size beingless than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing. However,the wear resistant particles may have an average particle size beinglarger than the thickness of the layer formed by the wear resistantparticles and the second thermoplastic material after pressing. Duringpressing, the wear resistant particles are pressed into the first foilsuch that the wear resistant particles do not protrude beyond an uppersurface of the layer, although the wear resistant particles having anaverage particle size exceeding the thickness of the layer formed by thewear resistant particles and the second thermoplastic material afterpressing.

The ratio between the size of the wear resistant particles and thethickness of the layer formed by the wear resistant particles and thesecond thermoplastic material after pressing may be less than 1.5:1.

Scratch resistant particles (not shown) may also be applied on the firstfoil 1. By scratch resistant particles are meant particles improving thescratch or scratch resistant properties of the first foil 1. The scratchresistant particles may be applied together with the wear resistantparticles, for example as a mix, or may be applied separately.Preferably, the scratch particles are arranged on an upper part of thelayer formed by the thermoplastic material 5 and the wear resistantparticles 4. The scratch resistant particles may be may be or comprisenano-sized silica particles, preferably fused silica particles. Thescratch resistant particles may be or comprise aluminum oxide.

The scratch resistant particles may be disc shaped particles, preferablyhaving a width/thickness ratio being equal or exceeding 3:1, morepreferably being equal or exceeding 5:1. Such disc-shaped particlesorientate along the surface of the foil, thereby improving the scratchresistance of the foil. The scratch resistant particles may have anaverage particle size of 1-50 μm, preferably 10-20 μm.

Additives may also be applied on the first foil 1, preferably togetherwith the second thermoplastic material 5. Additives may be plasticizers,stabilizers, lubricants, degassing agents, coupling agents,compatibilizers, crosslinking agents, etc.

In one embodiment, the first foil 1 is a PVC foil and the secondthermoplastic material 5 is PU. In one embodiment, the first foil 1 is aPVC foil and the second thermoplastic material 5 is PVC.

The different layers, i.e., the core 21, the decorative layer 22, thefirst foil 1, may be provided as continuous layers or being cut intosheets.

The core 21, the first foil 1 and the second thermoplastic material 5 inpowder form with the wear resistant particles 4 are thereafter adheredto each other, for example, pressed together, to form a building panel20. The first foil 1 and the second thermoplastic material 5 with thewear resistant particles 4 form a wear resistant foil 10 of the buildingpanel 20.

The wear resistant foil 10 is preferably transparent, or substantiallytransparent, for example, having a light transmittance index exceeding80%, preferably exceeding 90%.

The core 21, the first foil 1 and the second thermoplastic material 5are preferably pressed together in a pressing station 6. The press maybe a continuous or static press. The first and second foil may beadhered together by pressure alone, by heat and pressure, by pressureand adhesive, or by heat, pressure, and adhesive. Preferably, bothpressure and heat is applied in order to adhere the first and the secondfoil to each other. The pressing operation may for example be made as ahot-hot process, a hot-cold process, etc. Depending on the thermoplasticmaterials and process used, the pressure applied may be 5-100 bar,applied for example during 5-500 seconds. The temperature may be 80-300°C., such as 100-250° C., such as 150-200° C. The pressing may be madewith an embossed press matrix or press roller, such that an embossedstructure is formed in the wear resistant foil. As an alternative, thelayers may be adhered to each other by an adhesive such as glue, forexample, hot melt.

The second thermoplastic material 5 and the wear resistant particles 4form a layer, which may have a thickness of 0.01-1 mm, preferably asmeasured in the final product, for example, after pressing or extruding.Preferably, the layer formed by the second thermoplastic material 5 andthe wear resistant particles 4 has a thickness less than 0.5 mm, morepreferably less than 75 μm such as about 50 μm, preferably as measuredin the final product, for example, after pressing or extruding.

After adhering, the wear resistant particles are enclosed by the firstfoil and the second thermoplastic material. Although the wear resistantparticles and the second thermoplastic material may be applied as mix,during the pressing, the second thermoplastic material fuses andencloses the wear resistant particles. Preferably, the wear resistantparticles do not protrude beyond the surface of the layer formed thesecond thermoplastic material facing away from the first foil. Thereby,a wear resistant foil having a smooth surface can be formed.

A coating (not shown) may be applied on the wear resistant foil 10. Thecoating may comprise acrylate or methacrylate monomer or acrylate ormethacrylate oligomer. The coating may be radiation curing, such as UVcuring or electron beam curing.

As an alternative to a separate decorative layer 22, a print may beprinted directly on the top surface of core 21. The first foil 1 isthereby arranged directly on the core 21.

As an alternative to a separate decorative layer 22, the first foil 1may be a decorative foil. The first foil 1 may be printed, for exampleby digital printing, direct printing, rotogravure, etc. Preferably, theprint is provided on a side of the first foil 1 adapted to face the core21. The first foil 1 is thereby arranged directly on the core 21.

As an alternative to the decorative foil described above, the decorativelayer 22 may be formed of a thermoplastic material applied as a powderon the core. A print may be printed in the powder thermoplasticmaterial. The thermoplastic material in powder form may be polyvinylchloride (PVC), polyester, polypropylene (PP), polyethylene (PE),polystyrene (PS), polyurethane (PU), polyethylene terephthalate (PET),polyacrylate, methacrylate, polycarbonate, polyvinyl butyral,polybutylene terephthalate, or a combination thereof. The first foil 1is arranged on the powder layer and pressed together, as describedabove. The core 21 may be of the above described type.

Another alternative to the decorative foil described above is to apply athermosetting binder, preferably an amino resin and in powder form, andlignocellulosic or cellulosic particles for forming the decorative layer22 on the core 21. A print is may be printed in the powder layer, orpigments may be included. The core may be of the above described type.The first foil 1 is arranged on the powder layer are pressed togetherunder heat as described above, such that the thermosetting binder of thedecorative layer is cured.

Another alternatives for forming the decorative layer 22 are providing awood veneer layer, a cork layer, or a paper layer for forming thedecorative layer.

In one embodiment, the first foil 1 may be a decorative foil. The firstfoil 1 may be provided with a print, for example by digital printing,direct printing or rotogravure.

In one embodiment, both the decorative layer 22 and the first foil 1 areexcluded. The second thermoplastic material 5 in powder form and thewear resistant particles 4 are applied directly on the core. The secondthermoplastic material 5 is of the above described type. The core 21 isof the above described type. An upper surface of the core 21 may beprovided with a print, preferably a digital print. The wear resistantparticles 4 of the above described type may be applied together with thesecond thermoplastic material 5 as a mix or separately. Scratchresistant particles of the above described type may also be applied.

The second thermoplastic material 5 is fused, preferably by applyingheat and pressure, into a wear resistant foil 10′ comprising the wearresistant particles 4 arranged on the core 12 in a pressing operation asdescribed above.

It is contemplated that the core 21 may be excluded in the embodimentsdescribed with reference to FIG. 4. By adhering, for example, pressing,the decorative layer 22 and the second thermoplastic material 5 of theabove described type with the wear resistant particles 4, a decorativesubstrate having wear resistant properties is provided.

In addition to the building panel 20 described above with reference toFIG. 3, building panels 20 having another structure may also be providedby the methods described above.

According to one embodiment, which is shown in FIG. 5A, a building panel20 comprising a core 21 of the above described type and a wear resistantfoil 10′ manufactured according to the embodiment described withreference to FIG. 2. An upper surface of the core 21 may be providedwith a print 23, for example printed by for example by digital printing,direct printing or rotogravure. The wear resistant foil 10′ is arrangeddirectly on the core 21. The wear resistant foil 10′ is formed of thesecond thermoplastic material 5 of the above described type applied inpowder form and the wear resistant particles 4 of the above describedtype. The wear resistant particles 4 are preferably substantiallyhomogenously distributed in the wear resistant foil 10′.

According to one embodiment, which is shown in FIG. 5B, a building panel20 comprising a core 21 of the above described type and a wear resistantfoil 10 manufactured according to the embodiment described withreference to FIG. 1. Alternatively, the building panel 20 ismanufactured according to the embodiment described with reference toFIG. 4 wherein the decorative layer 20 is excluded. The wear resistantfoil 10 is arranged directly on the core 12. The wear resistant foil 10comprises the first foil 1 of the above described type and the secondthermoplastic material 5 of the above described type applied with thewear resistant particles 4 of the above described type. The first foil 1may be a decorative foil. The first foil 1 may be provided with a print23, for example printed by digital printing, direct printing orrotogravure. Alternatively, or as a complement, an upper surface of thecore 21 is provided with a print 23. The wear resistant foil 10 isarranged directly on the core 21. The wear resistant foil 10 may beproduced integrated with the method of producing the building panel, asdescribed with reference to FIG. 4, or as a separate process asdescribed with reference to FIG. 1.

According to one embodiment, the building panel 20 comprises a core 21of the above described type and a wear resistant foil 10′ formed of thesecond thermoplastic material 5 of the above described type and the wearresistant particles 4 the above described type applied directly on anupper surface of the core 21. The upper surface of the core 21 may beprovided with a print 23, for example printed by for example by digitalprinting, direct printing or rotogravure.

Any of the above described building panels may be provided with amechanical locking system. The mechanical locking system may be of thetype described in WO 2007/015669, WO 2008/004960, WO 2009/116926, or WO2010/087752, the entire contents of each is expressly incorporated byreference herein.

In all embodiments, the second thermoplastic material of the above typemay be applied in an extrusion process, which is shown in FIGS. 6A-B. InFIG. 6A, a first foil 1 is provided. The first foil 1 is of the typedescribed above with reference to FIGS. 1, 3, 5, 5A-B. In the embodimentshown FIG. 6A, the second thermoplastic material 5 of the abovedescribed type is mixed with the wear resistant particles 4 of the abovedescribed type. The second thermoplastic material 5 is preferablyprovided as granulates. The second thermoplastic material 5 in moltenform is applied on the first foil 1 comprising the first thermoplasticmaterial by an extruder 8. For example, the second thermoplasticmaterial 5 is applied on the first foil 1 by an extrusion process suchas extrusion lamination or extrusion coating.

As an alternative to mix the second thermoplastic material 5 with thewear resistant particles 4, the wear resistant particles 4 may beapplied separately form the second thermoplastic material 5 (not shown).The wear resistant particles 4 may be applied on the first foil 1 priorto applying the second thermoplastic material 5 by the extrusion processsuch as extrusion lamination or extrusions coating on the first foil 1.

The method to produce a wear resistant foil 10 by using an extrusiontechnique as described above with reference to FIG. 6A is alsoapplicable when forming a building panel corresponding to the embodimentshown in FIG. 4, which is shown in FIG. 6B.

In FIG. 6B, a first foil 1 and a core 21 are provided. The first foil 1and the core 21 are of the type described above with reference to FIGS.3, 4, and 5A-B. In the embodiment shown FIG. 6B, the secondthermoplastic material 5 of the above described type is mixed with thewear resistant particles 4 of the above described type. The secondthermoplastic material 5 is preferably provided as granulates. Thesecond thermoplastic material 5 in molten form is applied on the firstfoil 1 comprising the first thermoplastic material by an extruder 8. Forexample, the second thermoplastic material 5 is applied on the firstfoil 1 by an extrusion process such as extrusion lamination or extrusioncoating.

As an alternative to mix the second thermoplastic material 5 with thewear resistant particles 4, the wear resistant particles 4 may beapplied separately form the second thermoplastic material 5 (not shown).The wear resistant particles 4 may be applied on the first foil 1 priorto applying the second thermoplastic material 5 by the extrusion processsuch as extrusion lamination or extrusions coating on the first foil 1.

The core 21, the first foil 1 provided with the wear resistant particles4 and the second thermoplastic material 5 are adhered together forforming a building panel 20, for example, by pressing such ascalendaring as shown in FIG. 6B. Alternatively, the layers may beadhered to each other by means of an adhesive, such as hot melt.

It is also contemplated that the co-extruding may be used to form thewear resistant foil. The first foil comprising the first thermoplasticmaterial and a second foil comprising the second thermoplastic materialmay be formed by co-extruding the first and the second foil. The wearresistant particles may be mixed with the second thermoplastic material,or applied separately on the first and/or the second foil.

It is contemplated that there are numerous modifications of theembodiments described herein, which are still within the scope of thedisclosure. For example, it is contemplated that more than one wearresistant foil may be arranged on a core for forming a building panel.

For example, it is contemplated that after pressing, the boundariesbetween the first foil 1 and the layer formed of the secondthermoplastic material 5 in powder and the wear resistant particles 4may be less distinct.

EXAMPLES Example 1: Comparative Example

A PVC wear layer foil with a thickness of 0.3 mm was positioned on adecorative foil with a thickness of 0.1 mm. The two foils were laminatedon to a PVC core material using a temperature of 160° C., a pressure of20 bars and a pressing time of 40 seconds. The resulting product was aLVT product. The LVT product was found to have a wear resistance of 3200revolutions as tested in a Taber abrader.

Example 2: PVC Powder Composition on Foil

A PVC wear layer foil with a thickness of 0.3 mm was positioned on adecorative foil with a thickness of 0.1 mm. 150 g/m2 of a powdercomposition comprising 90 wt-% PVC and 10 wt-% Al₂O₃ was scattered onthe wear layer foil. The PVC powder composition and the two foils werelaminated on to a PVC core material using a temperature of 160° C., apressure of 20 bars and a pressing time of 40 seconds. The resultingproduct was a LVT product. The LVT product was found to have a wearresistance higher than 8000 revolutions as tested in a Taber abrader.

Example 3: PU Powder Composition on Foil

A PVC wear layer foil with a thickness of 0.3 mm was positioned on adecorative foil with a thickness of 0.1 mm. 150 g/m2 of a powdercomposition comprising 90 wt-% PU powder and 10 wt-% Al₂O₃ was scatteredon the wear layer foil. The PU powder composition and the two foils werelaminated on to a PVC core material using a temperature of 160° C., apressure of 20 bars and a pressing time of 40 seconds. The resultingproduct was a LVT product. The LVT product was found to have a wearresistance higher than 8000 revolutions as tested in a Taber abrader.

Example 4: PU Foil on PVC Foil

A printed decorative PVC foil having a thickness of 0.08 mm was arrangedon a core comprising three layers and having a thickness of 4 mm. A PVCwear layer having a thickness of 0.25 mm was arranged on the decorativePVC foil. Wear resistant particles in form of aluminum oxide wereapplied in an amount of 40 g/m2 on the PVC wear layer. A PU foil havinga thickness of 0.05 mm was arranged on the wear resistant particles andthe PVC wear layer. The different layers were pressed together in acold-hot-cold process. The pressure applied was 10 bar. The temperaturesapplied in the cold-hot-cold process were 50° C., 140° C., and 50° C.The product was pressed at 140° C. during 4 minutes. The total pressingtime was approximately 55 minutes. The resulting product was a LVTproduct. The LVT product was found to have a wear resistance higher than8000 revolutions as tested in a Taber abrader.

The invention claimed is:
 1. A method to produce a wear resistant foil,comprising: providing a first foil comprising a first thermoplasticmaterial, applying wear resistant particles and a second thermoplasticmaterial on the first foil, the second thermoplastic material beingapplied in powder form; and adhering the first foil to the secondthermoplastic material and the wear resistant particles and adhering thewear resistant particles to the second thermoplastic material to formthe wear resistant foil, wherein the adhering of first foil to thesecond thermoplastic material and the wear resistant particles and theadhering of the wear resistant particles to the second thermoplasticmaterial are by pressing, and wherein the wear resistant particles areenclosed by the first and second thermoplastic material and do notprotrude from a surface of the second thermoplastic material after beingadhered to the first foil.
 2. The method according to claim 1, whereinthe wear resistant particles are enclosed by the first foil and thesecond thermoplastic material after the first foil is adhered to thesecond thermoplastic material and the wear resistant particles.
 3. Themethod according to claim 1, wherein the wear resistant particles andthe second thermoplastic material are applied as a mix.
 4. The methodaccording to claim 1, wherein the first thermoplastic material comprisespolyvinyl chloride (PVC), polyester (PE), polypropylene (PP),polyethylene (PE), polystyrene (PS), polyurethane (PU), polyethyleneterephthalate (PET), polyacrylate, methacrylates, polycarbonate,polyvinyl butyral, polybutylene terephthalate, or a combination thereof.5. The method according to claim 1, wherein the second thermoplasticmaterial comprises polyvinyl chloride (PVC), polyester (PE),polypropylene (PP), polyethylene (PE), polystyrene (PS), polyurethane(PU), polyethylene terephthalate (PET), polyacrylate, methacrylates,polycarbonate, polyvinyl butyral, polybutylene terephthalate, or acombination thereof.
 6. The method according to claim 1, wherein thewear resistant particles comprise aluminium oxide.
 7. The methodaccording to claim 1, wherein the wear resistant foil is substantiallytransparent.
 8. The method according to claim 1, wherein the adhering ofthe first foil to the second thermoplastic material and the wearresistant particles and the adhering of the wear resistant particles tothe second thermoplastic material is by pressing without an adhesive. 9.The method according to claim 1, wherein the first thermoplasticmaterial is polyvinyl chloride and the second thermoplastic material ispolyurethane.
 10. A method to produce a building panel, comprising:providing a core, applying a first foil comprising a first thermoplasticmaterial on the core, applying wear resistant particles and a secondthermoplastic material on the first foil, the second thermoplasticmaterial being applied in powder form, and adhering the core, the firstfoil, the second thermoplastic material and the wear resistant particlescollectively to one another to form a building panel by pressing thecore, the first foil, the wear resistant particles, and the secondthermoplastic material together, wherein the wear resistant particlesare enclosed by the first and second thermoplastic material and do notprotrude from a surface of the second thermoplastic material after beingadhered to the first foil.
 11. The method according to claim 10, whereinthe wear resistant particles are enclosed by the first foil and thesecond thermoplastic material after the first foil is adhered to thesecond thermoplastic material and the wear resistant particles.
 12. Themethod according to claim 10, wherein the wear resistant particles andthe second thermoplastic material are applied as a mix.
 13. The methodaccording to claim 10, wherein the first thermoplastic materialcomprises polyvinyl chloride (PVC), polyester (PE), polypropylene (PP),polyethylene (PE), polystyrene (PS), polyurethane (PU), polyethyleneterephthalate (PET), polyacrylate, methacrylate, polycarbonate,polyvinyl butyral, polybutylene terephthalate, or a combination thereof.14. The method according to claim 10, wherein the second thermoplasticmaterial comprises polyvinyl chloride (PVC), polyester (PE),polypropylene (PP), polyethylene (PE), polystyrene (PS), polyurethane(PU), polyethylene terephthalate (PET), polyacrylate, methacrylate,polycarbonate, polyvinyl butyral, polybutylene terephthalate, or acombination thereof.
 15. The method according to claim 10, wherein thewear resistant particles comprise aluminium oxide.
 16. The methodaccording to claim 10, further comprising arranging a decorative layeron the core.
 17. The method according to claim 10, wherein thecollective adhering of the core, the first foil, the wear resistantparticles, and the second thermoplastic material is by pressing withoutan adhesive.
 18. A method to produce a wear resistant foil, comprisingproviding a carrier, applying wear resistant particles and a secondthermoplastic material on the carrier, the second thermoplastic materialbeing applied in powder form, adhering the wear resistant particles andthe second thermoplastic material to each other to form the wearresistant foil by pressing, and releasing the wear resistant foil fromthe carrier, wherein the wear resistant particles are enclosed by thesecond thermoplastic material and do not protrude from a surface of thesecond thermoplastic material.
 19. A method to produce a wear resistantfoil, comprising providing a first foil comprising a first thermoplasticmaterial, applying wear resistant particles and a second thermoplasticmaterial on the first foil, and adhering the first foil to the secondthermoplastic material and the wear resistant particles and adhering thewear resistant particles to the second thermoplastic material to formthe wear resistant foil, wherein the second thermoplastic material isapplied in molten form, wherein the wear resistant particles areenclosed by the first and second thermoplastic material and do notprotrude from a surface of the second thermoplastic material after beingadhered to the first foil.